SPEC 10. The Phytoplankton of Windermere

by C.S. Reynolds and A.E. Irish

Published by The Freshwater Biological Association, Ambleside, 2000, in collaboration with the NERC Centre for Ecology and Hydrology, Windermere

73 pages

ISBN 978-0-900386-65-7

Price £24.00

Windermere is the largest natural lake in England, visited by many thousands of tourists and perhaps the most comprehensively studied of any lake in the United Kingdom. This publication aims to provide a factual guide to almost a century's work on the microscopic plant life of Windermere – its phytoplankton. In so doing, it also provides a summarised case study of the effects of nutrient enrichment (or "cultural eutrophication") on phytoplankton populations and the results of subsequent nutrient control measures.

The booklet sets the scene by introducing the physical–chemical features of Windermere and its catchment, and the effects of the lake's light and temperature regime on algal physiology. The development of phytoplankton studies on Windermere is then described, with the sequence of events during 1965 being used as a baseline example for previous decades, and for assessing the changes that occurred in subsequent decades. This year proved to be a crucial year in the development of the lake, for shortly afterwards, Windermere began to receive direct discharges of nutrient-rich, secondary-treated sewage effluent. The booklet summarises the consequences for phytoplankton production, and the subsequent changes in the phytoplankton after restoration measures were introduced in 1992. Following on from this historical account, mechanisms governing the physiological ecology of phytoplankton in Windermere are discussed and the role of phytoplankton in the broader ecosystem of Windermere. Finally, longer-term climatic cycles are considered as revealed through paleolimnological reconstructions of past plankton activity and the kinds of responses that might be anticipated of global climatic changes. The text is enhanced by Dr Hilda Canter-Lund's superb illustrations of some common species of algae.